1. Field of the Invention
This invention relates to a composition for the treatment of a liquid, particularly a body of water, such as a swimming pool, spa or the like. The invention provides for the controlled release of the components of the composition for continuous and effective sanitisation and algae control to such a body of water.
2. Brief Description of Art
Compositions for the sanitization and algae control of bodies of water, such as swimming pools, spas and the like, are well known. It is particularly well known for one of the components of the composition to be calcium hypochlorite. Further, U.S. Pat. No. 5,164,109 to Wojtowicz, which is incorporated herein in its entirety by reference, describes a composition consisting essentially of calcium hypochlorite and a water soluble zinc salt. The US patent teaches that the control of algae is enhanced by use of such a composition and that the combination of these components tends to avoid a common problem, which is encountered in the use of other compounds, namely the reduction in the amount of available chlorine available for sanitization.
It would be a further advantage to provide a compound, such as that described above, having enhanced algicidal properties and which, in addition contains a agglomerating agent to facilitate the removal of suspended solids from the body of water and to thereby reduce biological load in the body of water (in this specification, an agglomerating agent is to be given a wide meaning and includes coagulating agents and flocculating agents). However, calcium hypochlorite is notoriously averse to combination with many other chemical compositions and the safety of the public must always be borne in mind in combining calcium hypochlorite with, or even housing calcium hypochlorite in proximity to, any other chemical components. Accordingly, there is a need for a chemical composition, which includes a sanitizer in the form of calcium hypochlorite (in anhydrous or hydrated form) together with an algicide comprising a soluble zinc salt (which may be either an inorganic or organic salt), and an agglomerating agent which may be safely combined therewith for storage, transport, sale and use in the treatment of a body of water.